My vote goes to high detergent mono grades such as Delo 400 SAE 40 weather permitting above 40F, or SAE 30 above freezing 32F/0C.
Mono grade engine oils are great at cleaning up ring zone deposits too.
I believe it is scrubbing action at the molecular level. I've tried SAE 40 on several engines that had ran on 5w30 for years. The engines ran very hot for an hour or two and smelled like something was burning. The oil turned black in a thousand miles in all cases. Engines that have been ran on HDEO's don't exibit that behavior.Just for my own understanding, why is this the case?
What product did you use to clean your Century?I guess if you have a lot of time and patience to wait for the clean up it might work. I found over the years that if you do in fact have an engine in need of being cleaned up, a product designed for cleaning up an engine is better suited for the job than trying with oil alone and short intervals. My 00 Century was a prime example of that.
I'd have to look in my records, it was either Kreen or MMO. I can say TDT 5W40 after about 30K miles didn't do much of anything.What product did you use to clean your Century?
OK I have both Kreen and MMO with Delo XLE 15w40 in the sumpI'd have to look in my records, it was either Kreen or MMO. I can say TDT 5W40 after about 30K miles didn't do much of anything.
Interesting. Update the threads with your findings if any.OK I have both Kreen and MMO with Delo XLE 15w40 in the sump
I'd guess it has to do with aromatic content.Just for my own understanding, why is this the case?
I plan to make a thread in the future. What I said might have sounded confusing. I own both MMO and Kreen (its a few years old but unopened, may need to order more). Currently only Delo 15w40 is in the sump. Towards the end of the OCI will put in some MMO and then try some flushes, whether a large portion of MMO, Rislone, Kreen. I will try them all until the motor is clean and see if the ticking and slapping sounds go away.Interesting. Update the threads with your findings if any.